I\'ve found a few related questions, like Python vs. Perl (now deleted) and Is Perl Worth it? (now deleted), but I can\'t seem to find anything that directly a
Plenty of shops - including on Wall Street - heavily use Perl and will continue to do so.
However, I have never seen a PHP or Python used in this industry (not saying it is not used, but that I never encountered. Purely personal anecdote. Nor have I EVER heard any conversation of "Perl can not do X that Python can, let's use Python").
Perl6 is irrelevant to job picture.
Many shops are still on 5.8 or G-d forbid 5.6
More importantly, perl5 continues to evolve, including with features/ideas from Perl6. See Perl 5.10 and 5.11
Plus evolution includes really cool framework like Moose etc...
I can probably come up with more bullets later, but the summary is that no, having a Perl job will in no way negatively affect your career prospects.
However, knowing nothing but Perl may affect it negatively, so make sure you know Java, C#, C++ or something besides dynamic interpreted languages. Not many shops would hire "Perl Only" developer, even if they gladly hire "Perl + other stuff" ones.